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Research to Produce Ethanol from Seaweed Biomass Cladophora sp

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材料科学与工程（中英文B版） 2013年第10期3卷 670-676页

作者： Vo Thanh trung Bui Minh Ly le Nhu Hau Nguyen Thanh Hang Nhatrang Institute of Technology Reasearch and Application Nha Trang Viet Nam Ha Noi University of Science and Technology Ha Noi Viet Nam

Biomass seaweed Cladophora sp. (BSC) included Cladphora socialis, Cladophora prolifera, Cladophora crupila, which was hydrolysised in dilute sulfuric acid and enzymatic hydrolysis of cellulase. BSC was treated by dilute sulfuric acid at concentration of 0, 0.5%, 1%, 2%, 3%, 4%, 5%, 6% (v/v) (v volume) in autoclave respectively at 121 °C at time 20, 40 and 60 minute, with the rate between seaweed and solution acid of 1/10(w/v) (w weight). Beside, BSC was pretreated in dilute sulfuric acid at 0.5%(v/v) at 121 °C in 20 minute, after it was treat at concentrations 0, 0.2, 0.4, 0.6, 0.8, 1 ml/g with the enzymatic hydrolysis consisted of cellulase in control (50 °C, pH 5.0, 24 h). The results showed that, total sugar contents of two methods are the same, but sugar content was varied by treatment time of heat. Rates of acid 4%; 5%, 6% (v/v) and 0.8; 1 ml/g have high sugar content within the range of 42.38-48.51 mg/ml. 400 ml of hydrolysis solution was fermented by Saccharomyces cerevisiae at 30 °C for 72 h. After fermentation, 5% ethanol solution was identified for the first 100 ml evaporate solution. BSC is easily hydrolyzed and fermented to ethanol, this shows excellent prospects as a potential feedstock for the production of bioethanol.

关键词：乙醇溶液刚毛藻生物质 Alcalase碱性蛋白酶海藻生产水解纤维素总糖含量

Molybdate Doped Polypyrrole： Preparation, Properties and Application

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材料科学与工程（中英文A版） 2013年第5期3卷 321-328页

作者： Ha Manh Hung le Minh Duc Tran Vinh Dieu Vu Quoc trung Faculty of Chemistry Hanoi National University of Education Cau Giay District Hanoi Vietnam Faculty of General Education Hanoi University of Mining and Geology Dong Ngac Tu Liem Hanoi Vietnam Faculty of Chemical Engineering Danang University oJ l"echnology Lien Chieu District Danang Vietnam Centre of Polymer Research Hanoi University of Science and Technology Hai Ba Trung District Hanoi Vietnam

Molybdate doped-polypyrrole (PPy) was electropolymerised on the mild steel surface. The morphology of polymer film was studied with scanning electron microscopy (SEM). The chemical structure of polymer was characterized with Raman spectroscopy. The presence of molybdate doped inside polypyrrole was identified by EDX spectra. The thermal analysis (TGA) showed that polypyrrole was stable up to 500 °C. The corrosion protection of the polymer film was investigated by electrochemical methods showing that the polymer film acted as a barrier layer and molybdate as an inhibitor for corrosion protection of metal. Molybdate dopant was the key component of "self-healling" polypyrrole film.

关键词：掺杂聚吡咯钼酸盐扫描电子显微镜防腐蚀保护制备应用性能聚合物膜

Upconversion luminescence of Gd2O3:Er3+and Gd2O3:Er3+/silica nanophosphors fabricated by EDTA combustion method

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Journal of Rare Earths 2019年第11期37卷 1126-1131页

作者： le Quoc Minh Tran Kim Anh Nguyen Duy Hung Pham Thi Minh Chau Nguyen Thi Quy Hai Ho Van Tuyen Vu Thi Thai Ha Vu Duc Tu Wieslaw Strek Institute of Theoretical and Applied Research Duy Tan UniversityDa Nang 55000Viet Nam Advanced Institute for Science and Technology Hanoi University of Science and Technology1 Dai Co VietHai Ba TrungHanoiViet Nam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc Viet RoadCau Giay DistrictHanoiViet Nam Institute of Low Temperature and Structure Research Polish Academy of Science 2 OkolnaWroclawPoland

Gd2O3:Er^3+nanophosphors were fabricated by the combustion method in presence of Na2 ethylene diamine tetra acetic acid(EDTA-Na2)as fuel at not high temperature(≤350℃)within a very short time of 5 *** added concentration of Er^3+ions in Gd2O3 matrix was changed from 0.5 mol%to 5.0 mol%.The X-ray diffraction pattern of samples indicates the monoclinic structure of Gd2O3:Er^3+.The morphology and chemical composition analysis of the Gd2O3:Er^3+samples are characterized by a field emission scanning electron microscope(FESEM)and a Fourier-transform infrared spectrometer(FTIR).The photoluminescence(PL),photo luminescence excitation(Ple)and upconversion(UC)at room temperature of the prepared materials with different concentrations of Er^3+were *** PL of Gd2O3:Er^3+nanomaterials are shown in visible at 545,594,623,648,688 nm under excitation at 275 *** emission bands from transitions of Er^3+from 2P3/2 to 4F9/2 are observed,UC luminescent spectra of the Gd2O3:Er^3+/silica nanocomposites under 976 nm excitation show the bands at 548 and 670 *** influence of excitation power at 980 nm for transitions were measured and *** results indicate that the upconversion process of Gd2O3:Er^3+/silica is two photons absorption *** low temperature dependence of UC luminescent intensities of the main bands of Gd2O3:Er^3+was investigated towards development of a nanotemperature sensor in the range of 10-300 K.

关键词： Upconversion luminescence Gd2O3:Er3+ Gd2O3:Er3+/silica Nanophosphors EDTA combustion Rare earths

A comparative analysis of weight-based machine learning methods for landslide susceptibility mapping in Ha giang area

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Big Earth Data 2023年第4期7卷 1005-1034页

作者： Thanh Trinh Binh Thanh Luu Trang Ha Thi le Duong Huy Nguyen Trong Van Tran Thi Hai Van Nguyen Khanh Quoc Nguyen Lien Thi Nguyen Faculty of Computer Science Phenikaa UniversityYen NghiaHa DongHanoi 12116Vietnam Phenikaa Research and Technology Institute(PRATI) A&A Green Phoenix Group JSCNo.167 Hoang NganTrung HoaCau GiayHanoi 11313Vietnam Northwestern Geological Division General Department of Geology and Minerals of VietnamHanoiVietnam Youth union office Thuyloi University175 Tay SonDong DaHanoiVietnam Center of Remote Sensing and Geohazards Vietnam Institute of Geosciences and Mineral ResourcesHanoiVietnam

Landslide susceptibility maps (LSMs) are very crucial for planningpolicies in hazardous areas. However, the accuracy and reliability ofLSMs depend on available data and the selection of suitable *** study is conducted to produce LSMs by combinations of machinelearning methods and weighting techniques for Ha giang province,Vietnam, where has limited data. In study area, we gather 11 landslideconditioning factors and establish a landslide inventory *** the weights of classes (or factors) is very important toprepare data for machine learning methods to generate LSMs. Wefrst use frequency ratio (FR) and analytic hierarchy process (AHP)techniques to generate the weights. Then, random forest (RF), supportvector machine (SVM), logistic regression (LR), and AHP methods arecombined with FR and AHP weights to yield accurate and reliableLSMs. Finally, the performance of these methods is evaluated by fivestatistical metrics, ROC and R-index. The empirical results have shownthat RF is the best method in terms of R-index and the five metrics, *** rate (0.9661), FP rate (0.0), ACC (0.9835), MAE (0.0046), and RMSE(0.0350) for this study area. This study opens the perspective of weightbasedmachine learning methods for landslide susceptibility mapping.

关键词： Landslide logistic regression random forest SvM Vietnam

Influence of Process Factors on Electrode Wear Rate when EDM 90CrSi Steel using Graphite Electrodes

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Journal of Environmental Science and Engineering(B) 2023年第5期12卷 230-235页

作者： Tran Huu Danh le Thi Phuong Thao Nguyen Thi Quoc Dung Vu trung Tuyen Luu Anh Tung Vinh Long University of Technology Education Vinh Long City 85110Vietnam Thai Nguyen University of Technology Thai Nguyen city 251750Vietnam National Research Institute of Mechanical Engineering Hanoi City 511309Vietnam

The findings of a study on the optimization of Electric Discharge Machining(EDM)procedure for processing cylindrically shaped components with graphite electrodes are presented in this *** steel 90CrSi was the material of choice for the study’s ***,the Electrode Wear Rate(EWR)was chosen as the optimization problem’s objective *** experiment using the Taguchi design was conducted to address this ***,experiments were created and their outcomes were analyzed using the Minitab R19 *** impact of the input process factors on EWR was investigated,including the powder concentration,the pulse on and off times,the servo current,and the servo ***,the best process variables for a minimal EWR were provided.

关键词： EDM process factor EWR 90CrSi.

It Takes Two to Tango： Entrepreneurship and Creativity in Troubled Times--Vietnam 2012

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Sociology Study 2012年第9期2卷 662-674页

作者： Nancy K. Napier Dang le Nguyen Vu Quan Hoang Vuong Boise State University USA/Aalborg University Denmark trung Nguyen Coffee Group Vietnam Universite Libre de Bruxelles Belgium

This study focuses on perceived values of entrepreneurship and creativity within a turbulent environment. The initial hypothesis is that a typical entrepreneurial process carries with its ＂creativity-enabling elements＂. In a normal situation, businesses focus on optimizing their resources for commercial gains, thus perceptions about values of entrepreneurial creativity are usually vague. However, in difficult times, the difference between survival and failure may be creativity. This paper examines many previous findings on entrepreneurship and creativity, and suggests a highly possible ＂organic growth＂ of creativity in an entrepreneurial environment and reinforcing value of entrepreneurship when creativity power is present. In other words, the authors see each idea reinforcing the other. The authors survey Vietnamese firms during the chaotic year of 2012 to learn about the ＂entrepreneurship-creativity nexus＂, looking at influential cultural values, namely risk tolerance, relationship, and dependence on resources--to assess how they influence entrepreneurial decisions. A set of 137 qualified responses was obtained for this statistical examination. A categorical data analysis is performed to confirm that creativity and entrepreneurial spirit could hardly be separate, for both entrepreneurial and accomplished companies. Although the most important factor during implementation is still ＂relationship＂, business people are increasingly aware of the need of creativity/innovation in troubled times.

关键词： Creativity entrepreneurship economic transition Vietnam

Green synthesis of three-dimensional magnesium ferrite/titanium dioxide/reduced graphene from Garcinia mangostana extract for crystal violet photodegradation and antibacterial activity

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Journal of Semiconductors 2023年第12期44卷 111-124页

作者： Tong Hoang Lin Che Quang Cong Nguyen Thanh Hoai Nam Hoang An Nguyen Duy Hai Ton That Buu Thoi le Nhat Binh Hoang le Minh Lam Thanh Ngan Hoang Thuy Kim Ngan Du Chi Vi Ta Dang Khoa Nguyen Huu Hieu VNU-HCM Key Laboratory of Chemical Engineering and Petroleum Processing(Key CEPP Lab)Ho Chi Minh City University of Technology(HCMUT)268 Ly Thuong Kiet StreetDistrict 10Ho Chi Minh CityVietnam Faculty of Chemical Engineering Ho Chi Minh City University of Technology(HCMUT)268 Ly Thuong Kiet StreetDistrict 10Ho Chi Minh CityVietnam Vietnam National University Ho Chi Minh City(VNU-HCM) Linh Trung WardThu Duc CityVietnam

In this study,three-dimensional porous magnesium ferrite/titanium dioxide/reduced graphene oxide(Mg Fe_2O_(4)-GM/TiO_(2)/rGO(MGTG))was successfully synthesized via green and hydrothermal-supported co-precipitation methods using the extract of Garcinia mangostana(***)as a reducing *** characterization results indicate the successful formation of the nano/micro Mg Fe_(2)O_(4)(MFO)and TiO_(2) on the structure of the reduced graphene oxide(rGO),which can also act as efficient support,alleviating the agglomeration of the nano/micro MFO and TiO_(2).The synergic effects of the adsorption and photodegradation activity of the material were investigated according to the removal of crystal violet(CV)under ultraviolet *** effects of catalyst dosage,CV concentration,and p H on the CV removal efficiency of the MGTG were also *** to the results,the CV photodegradation of the MGTG-200 corresponded to the pseudo-first-order kinetic *** reusability of the material after 10 cycles also showed a removal efficiency of 92%.This happened because the materials can easily be recollected using external *** addition,according to the effects of different free radicals·O_(2)^(-),h^(+),and·OH on the photodegradation process,the photocatalysis mechanism of the MGTG was also thoroughly *** antibacterial efficiency of the MGTG was also evaluated according to the inhibition of the Gram-positive bacteria strain Staphylococcus aureus(***).Concurrently,the antibacterial mechanism of the fabricated material was also *** results confirm that the prepared material can be potentially employed in a wide range of applications,including wastewater treatment and antibacterial activity.

关键词： magnesium ferrite titanium dioxide reduced graphene oxide Garcinia mangostana photodegradation antibacterial

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胡志明市中央公园

现代装饰 2019年第10期 114-117页

作者： Dong Viet Ngoc Bao Nguyen Xuan Man Vu Ngoc Anh Do Thi Duong Thi Nguyen Phuc Anh Thu Pham Duy Bao Long Nguyen Truong Ngan Cao trung Nguyen Trinh Tien Vinh le Thuy Ngan Trinh Duc Tri Bui Quang Khanh Pham Thi Ngoc Ha Chris Bosse 郭映琴(编译) 方钰丹 LAVA&ASPECT Studio

LAVA联合ASPECT Studio赢得了越南胡志明市中央公园的国际竞赛,该项目计划于2020年开始建设。同时,LAVA将为该项目在未来三年的开发和建设提供服务。设计团队和合作方将共同创造一个真实存在的场所,搭建连接过去和未来的桥梁,建立起人... 详细信息

LAVA联合ASPECT Studio赢得了越南胡志明市中央公园的国际竞赛,该项目计划于2020年开始建设。同时,LAVA将为该项目在未来三年的开发和建设提供服务。设计团队和合作方将共同创造一个真实存在的场所,搭建连接过去和未来的桥梁,建立起人类、自然与科技之间的联系。摒弃了传统拘谨的设计格局,LAVA的设计是随性的、多功能的、友好的、互相联系且贯通的。

关键词：中央公园胡志明市

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2030年后越南的中等强国目标及外交远景

南亚东南亚研究 2019年第3期 59-75,154,155页

作者：黎庭静左荣全越南外交学院南海院

近年来,越南革新开放进一步深入,经济呈加速发展态势,累积起来的综合国力也随之上升,越南在地区和国际舞台上更趋活跃。现在是否已经到了重新定位越南国际地位和角色的时候?不同的人可能有不同回答,但肯定的回答居多则是毋庸置疑的。到... 详细信息

近年来,越南革新开放进一步深入,经济呈加速发展态势,累积起来的综合国力也随之上升,越南在地区和国际舞台上更趋活跃。现在是否已经到了重新定位越南国际地位和角色的时候?不同的人可能有不同回答,但肯定的回答居多则是毋庸置疑的。到底该怎么重新定位越南的国力?越南学者中提及最多的定位方式是"中等强国"。其中,以越南外交学院南海院院长黎庭静博士2018年6月在《国际研究》杂志上发表的《2030年后越南的中等强国目标及外交远景》一文最为详实和客观,比较全面地回答了上述疑问。该文主要包括理论基础、实践经验和2030年后越南外交的相关问题及建议三部分。前2部分探讨国际上中等强国的概念及实践经验,行文中交替使用"中等强国"和"中等国家"两个概念,"中等国家"是一个更宽泛也更中性的概念,"中等强国"范围要更小、敏感度更高一些,越南的目标定位不是平常的中等国家,而是中等强国。"中等强国不是正式称谓,而只具有对各种外交活动的一种内部启发作用"。第三部分阐述了为什么将时间点选在2030年,并从实力-能力、外交行为/应对方式-国际影响、越南本色-品牌三个方面说明届时越南完全具备实现中等强国目标的条件。文章最后就实现中等强国目标后外交、战略等相关领域面临的挑战提出了三方面的建议。结论是越南将充分汇聚各种基本条件(能力、行为、本色),以便可以提出成为中等强国的目标,并在2030年后像一个中等强国那样发挥作用。

关键词：越南外交国际一体化中等强国目标远景